What mothers-to-be eat around the time of conception may influence the epigenome of her child, researchers led by Branwen Hennig from the MRC International Nutrition Group at MRC Keneba in The Gambia and the London School of Hygiene and Tropical Medicine report in Nature Communications.
To see how human maternal diet affects DNA methylation in children, the researchers turned to a group of rural Gambian women whose diet fluctuates with the seasons: During the rainy season, they eat more vegetables, though receive fewer calories overall, while during the harvest season they receive more calories, but fewer vitamins from those foods.
Hennig and colleagues focused on a set of about a dozen biomarkers that included key methyl-donor pathway substrates, cofactors, vitamins, and intermediary metabolites to gauge the women's diet. Then in the infants, they examined CpG methylation at seven metastable epialleles, regions where DNA methylation is established early in development and then maintained in differentiated tissue.
From this, the researchers noted that there were seasonal fluctuations in those 13 biomarkers in the plasma of Gambian women, and that infants conceived during the rainy or hungry season had higher levels of DNA methylation at that sites than those conceived during the dry or harvest season.
"Our results represent the first demonstration in humans that a mother's nutritional well-being at the time of conception can change how her child's genes will be interpreted, with a lifelong impact," Hennig says in a statement, according to LiveScience.
Eventually, co-author Andrew Prentice from the London School of Hygiene and Tropical Medicine says an "optimal diet for mothers-to-be that would prevent defects in the methylation process" could be developed. "[O]ur research is pointing towards the need for a cocktail of nutrients, which could come from the diet or from supplements," he says.